Drop-feeding device



A. L. SCHRAM DROP FEEDING DEVICE July 5 1927. v 1,634,560

Filed Nov. 17. 1924 3 Awzw-ro 34 A 4 [AW/V05? Z. 60/24 7 ,irrx

Patented July 5, 1927.

UNITED STATES PATENT OFFICE.

I ALEXANDER L. SCREAM, OF HILLSBORO, ILLINOIS, ASSIGNOE, BY MESNE ASSIGN- MENTS, TO BALL BROTHERS COMPANY, OF MUNCIE, INDIANA, A CORPORATION OF INDIANA.

' DROP-FEEDING DEVICE.

Application filed November 17, 1924. SeriaLNo. 750,289.

contained in the forward portion thereof,

against chilling thereby allowing the issuing stream of glass to descend vertically instead of being bent out of vertical alinement by the forward or front surface of the'stream being cooler than the rear portion, and thus not flow ng as freely as the rear portion and pulling tie stream out of vertical.

A still further object is to construct a drop feeding device in which the issuing stream is maintained at a uniform temperature throughout its circumference or outer surface, and in which the severed end of the stream is drawn upward into and reheated by the oncoming glass, thus assuring a mold charge of substantially uniform temperature throughout.

In the drawings Fig. 1 is a side elevation of a portion of a. glass furnace with my improvement attached thereto, parts being brokenaway and in section;

Fig. 2 is a front elevation of the boot and its. appurtenances;

Fig. 3 is a horizontal longitudinal section of the boot taken on the line 33 of Fig. 1 with the furnace'and supporting frame removed;

Fig. 4 is a fra-gmental vertical longitudinal section of my spout;

Fig. 5 is a longitudinal vertical section enlarged illustrating one methodof cutting means for" severing the glass stream.

In the construction of my device I employ a glass furnace which is provided along its front face with buck-staves 11, to these staves is attached a harness 12. Resting in the harness 12 is a trough 13 which is in alinement with the opening 14 formed in the front wall of the glass furnace and permits the glass to pass directly into the trough. The trough is provided with a bottom 15, side walls. 16, and a front wall 17 which. is preferably curved as illusside walls 16 of the trough are walls 18 which are provided with covering plates 19 and 20, and supportedby the front wall 17 is a hood 21. -This completely incases and trated in Figs. 3, 4 and5. Resting on the closes the opening 14 and prevents any cold air from entering the furnace.

The side walls 18 and cover 20 are provided with hollow bosses 22 through which flames are projected to assist in maintaining proper temperature within the boot.

The cover 20 and hood 21 are provided adjacent their abutting edges with a cut away portion which permits the plunger or stopper 23 to pass freely therethrough and enter the boot. To the upper end of the stopper is .pivotally attached a link 24,

the oppos te end of the link is pivotally and slidably secured in a slot 25 formed in one end of the lever 26. This leveris pivotally supported intermediate its ends in a bifurcated bracket 27 which is carried by the rod 28, the rod in turn being supported by the harness 12.

To the end 29 of the lever 26is attached an operating means 30 which may be either a chain and handle, or other means by which the lever can be oscillated manually or the same may be mechanically operated.

v The trough 13 has its front wall 17 thickened by means of a crescent shaped projection 31 which extends inwardly and which becomes highly heated by contact with the molten glass and the temperature within the glass furnace and prevents any chilling of glass in the forward end of the trough, which is in the form of a substantially crescent shaped block 32, which has its upper concave edge rounded, as illustrated in Fig. 4, which is placed in position abutting the front wall while assen'ibling the boot. I The bottom 15 of the trough is provided with an opening 33 which is preferably circular and which is located adjacent the thickened portion of the forward end of the boot, as illustrated in Fig. 4 and which is adapted to receive a bushing 34. This bushing is made of various sizes as toits outlet opening and serves to assist in regulating the stream of glass issuing from the boot. Secured, preferably to the harness and, directly below the opening in the boot is (ill a plate which is provided with a central opening 36, this opcn'ng being located directly beneath the opening 33. The plate 3.5 is also provided with Lshaped or grooved ribs 37 which slidably support a cutter or severing means 38. These means are prefcrably operated by an air cylinder 39 which is synchronized with the movement of the mold table, although the same may be operated by hand if desired. Neither do I desire to lmit myself to the specific construction of severing means shown as there are various structures by which the severing of the stream of glass can be accomplished without departing fr m the spirit of my invention.

The plunger of a or diameter larger than the opening; formed through the bushing so that the flow of glass theretlirough may be completely stopped. The lower end of the plunger maybe either a plane surface or it may be convened or dished, but when making the end convened the upper end of the bushing 34 will have to be made concave so that a tight joint can be obtained, but in all events the major portion of the plunger solid and imperforate.

By thickeningthe front wall 1? in the manner illustrated, I insulate the glass in the trough from the outside air so that the same will not'b'ecome readily chilled and cause the glass to flow unevenly through the opening in tne bushing In this way I am always sure of a stream passing downwardly vertically which would not be the case were one portion of the outer surface chilled or, in other words, of a different temperature than. the remainder of the outside surface. This will result in the chilled portion of the stream flowing less freely than the remainder and bending the stream out of the perpendicular thereby making it difiicult to accurately center the stream, but where the stream descends vertically, as by my improvement, this centering is simplified and there are no oscillations bacl; and forth in the stream as is the case where a chilled portion exists along one part of the outer skin of the issuing stream.

By my peculiar construction of boot, practically the on y glass which enters the opening in the bushing 34- comes from the rear and sides where it is maintained in a highly heated condition by means of the heating jets which enter through the openings formed in the bosses 22 and there is no tendency for the glass to pocket in a dead space and become partially chilled and then passing through the opening in the bushing, as is the case where the insulating block is not present in the boot. As in this case glass in passing through the orifice or opening in the bushing is drawn from the front of the boot rearwardly along the bottom and the top or hot glass flows forward becoming chilled and tion, the plug 23 then inserted and attached to the link 24. The severing means is then secured in the proper pos tion beneath the bushing and the heat started in the furnace, the glass then nelts and passestothe boot filling it up to the glass level, as indicated in Fig. 1.. The heating jets are then ignited, the glass forming machine run into position beneath the boot and the device is ready to operate.

The end 29 of the lever 26 is depressed by any suitable mechanism, either mechanical or manual, and the plunger 28 raised to permit the glass to issue from the opening in the bushing in a relatively heavy stream. The end 29 of the lever 28 is then permitted to raise, permitting the plunger 23 to move downward. This downward movement assists in forcing out the molten glass through the orifice in the bushing for a certain period of its descent, after which it tends to gradually reduce the stream or rather the amount of glass supplied thereto. 'This' permits the stream to become attenuated. The .downward movement of the plunger is continued until it comes in contact with the bushing, at this point the st-ream' issuing from the orifice in the bushing has arrived at its extreme attenuation and. simultaneous with the contact of the plunger and bushing the severing means is operated and the stream cut as near the underside of the trough as possible. A gob or globule of glass with a depending attenuated: neck now remains fast to the underside or end of the plunger, the attenuated neck, however, as soon as the severing means have cutt-heret-hrough, immediately draws up into the larger mass suspended. from the bottom end of the plunger. The end 29 of the lever 26 is now depressed rather rapidly and due to the viscosity of the glass, an opening is left therein which permits the small globule of glass still attached to the plunger to be drawn upward. As the plunger rises and the space between the bushing and plun ger become greater, the molten glass again flows through the opening with gradually increasing rapidity and before the plunger has reached its uppermost position, the globule of glass which has depended from the underside of the plunger is completely surrounded and absorbed into the molten glass within the trough 13 so that I am enabled to get'glass of substantially a uniform temperature Hill throughout, into the mold, there being no glass protruding from the furnace to be chilled or resting in a gathering cup during the shifting of the molds.

I have also discovered that by having the stream of glass of uniform surface temperature throughout, I get a much more perfect article because the glass after being delivered to the mold and having its center opened will have no cold spots and in the blowing to compete the article, the glass will flow evenly in all directions so that the finished article will have a wall of uniform thickness throughout. I have also discovered that where the surface temperature of the glass is uneven that it will not flow evenly when it is blown and consequently an article is formed which has thick spots or portions of the wall, thus making an imperfect article and one which is liable to have strain set up in the walls when cooling which will cause it to break readily.

Having fully described my invention, what I claim is:

1. A drop feeding device comprising-a trough having a bottom, side walls and a front wall and in direct communication with a glass furnace, a discharge orifice formed in the bottom of said trough and spaced from the front and side walls, a bushing located in said discharge orifice, a crescentshaped block located in said trough and abut-ting the front wall, and a covering for said trough.

2. A drop feeding device comprising a trough in direct communication with a glass furnace and having a bottom, side walls and a front wall, a discharge orifice formed in the bottom of said trough and spaced from the front and side walls, a bushing located in said discharge orifice, a crescent shaped block located in said trough and abutting the front Wall, a covering for said trough, and means extending through said covering for controlling the flow of molten glass through said discharge orifice.

3. A drop feeding device comprising a trough having a bottom, side walls and a from the front and side walls, a bushing located in said discharge orifice, a crescentshaped block having a rounded upper edge located in said trough and abutting the front wall, a covering for said trough, and means for controlling the flow of glass through said discharge orifice, said means extending vertically through the cover and havingits lower end located above the bushing.

5. A drop feeding device comprising a trough having a level bottom, side walls and a front wall and in direct communication with aglass furnace, a discharge orifice formed in the bottom of said trough and spaced from the front and side walls, a bushing located in said discharge orifice, a crescent-shaped block located in said trough and abutting the front wall, and a covering for said trough.

6. A drop feeding device comprising a trough having alevel bottom, side walls and a front wall and in direct communication with a glass furnace, a discharge orifice formed in the bottom of said trough and ing located in said discharge orifice, a crescent-shaped block located in said trough and abutting the front wall, a covering for said trough, and means extending vertically through the cover and in alignment with the spaced from the front and side walls, a bushdischarge orifice for controlling the flow of molten glass through said orifice.

In testimony whereof, I have signed my name to this specification.

ALEXANDER- L. SCHRAM. 

